1. Field
The present general inventive concept relates to a transfer belt driving controller and an electrophotographic image forming apparatus having the same, and more particularly, to a transfer belt driving controller that detects a speed of a transfer belt and feeds back information to a driving motor based on a result of the detection to control constant velocity drive of the transfer belt, and an electrophotographic image forming apparatus having the same.
2. Description of the Related Art
An electrophotographic image forming apparatus is an apparatus for forming a desired image by receiving digital image signals corresponding to the desired image, forming an electrostatic latent image on a photo conductor by using an exposer, such as a laser scanning unit (LSU), developing the electrostatic latent image into a toner image by using a toner, transferring the toner image to a printing medium, and fusing the toner image to the printing medium by applying heat and pressure to the toner image.
A single-pass type color image forming apparatus generally includes four photoconductive drums, four exposers that form electrostatic latent images on the four photoconductive drums, and four developers that develop the electrostatic latent images formed on the four photoconductive drums by respectively supplying black (K), cyan (C), magenta (M), and yellow (Y) toners thereto. The four photoconductive drums contact an intermediate transfer belt. A color toner image is formed by reiteratively transferring the black (K), cyan (C), magenta (M), and yellow (Y) toner images developed on the four photoconductive drums to the intermediate transfer belt. A desired color image is printed by transferring and fixing the color toner image to a printing medium.
In a color image forming apparatus, since an image is temporarily formed on a surface of a transfer belt before the image is transferred to a printing medium, change of a linear velocity of a transfer belt is an important factor directly affecting quality of a printed image. A linear velocity of a transfer belt is changed by a driving power transmission component for transmitting a driving power from a driving source to a driving roller. As stated above, although precision of the final gear connected to a driving roller for transmitting driving power to a transfer belt and irregular loads of photoconductive drums connected to the transfer belt cause change of a linear velocity of the transfer belt and directly affect quality of an image, it is very difficult to maintain satisfactory precision of related parts.
Therefore, it is necessary to prevent color mis-registration by minimizing change of a linear velocity by accurately detecting change of a linear velocity of a transfer belt and feeding back information to a driving motor based on a result of the detection.